FIELD : medicine.SUBSTANCE : invention relates to medicine, particularly to cardiovascular surgery. Access to the prosthetic mitral valve (MV) is made through interatrial septum (IRS), excision of the MV, implantation of MV prosthesis. When this prosthesis MV fixed supraannular type on the pads to MV native fibrous ring (FR). Mitral-aortic (M-A) contact zone is fixed to IRS from the right atrial cavity side. Wedge patch of xenopericardum is sutured in IRS in the area of access formed. Method allows to ensure the possibility of implantation of MV prosthesis with active infective endocarditis, as well as to reduce the risk of formation of paraprosthetic fistulas, which is due to the partial implantation of the prosthesis to IRS, thus allowing to obtain its stable fixation.EFFECT : possibility of implantation of MV prosthesis with pathological change in the tissue of M-A contact keeps off the risk of a possible rupture of the atrium wall by fixing prosthesis to IRS healthy tissues and not to dystrophically modified M-A contact; in addition, by eliminating stitches in the area of active infectious process (M-A contact), the risk of bleeding is minimized; due to lack of use of foreign material for reconstruction of native MV FR risk of complications associated with the use of foreign material is eliminated.4 cl, 1 ex